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Simon_P
New Member
September 30, 2025
Question

Fortinet Virtual Adapters Showing as Unknown Device

  • September 30, 2025
  • 2 replies
  • 774 views

Hello,

 

I recently updated FortiClient on a laptop to version 7.4.3.1790. Since then, the VPN has been unable to connect, and the Fortinet virtual adapters show as "Unknown Device" in the Windows 11 Device Manager.

 

Every time I reboot the laptop, a FortiClient popup appears and says that FortiClient drivers have been installed that require a restart to finish. Each restart adds two more Unknown Devices in Device Manager. 

 

A reinstall or repair of FortiClient doesn't fix the issue. I've tried reinstalling Visual C++ 2015-2022, but no luck there either.

 

The two virtual adapters are supposed to show as:

- Fortinet SSL VPN Virtual Ethernet Adapter

- Fortinet Virtual Ethernet Adapter (NDIS 6.30)

 

How can I fix these two virtual adapters?

 

Thanks,

Simon

2 replies

Anthony_E
Staff
Staff
October 3, 2025

Hello Simon,

 

If Fortinet virtual adapters are showing as unknown devices, it may be due to the behavior of the Persistent Agent with virtual adapters. Here are steps to address this:

  1. Check FortiNAC Version: Ensure you are using a version that addresses known issues with virtual adapters. For FortiNAC 8.8.3/Agent 5.2.4 and lower, consider upgrading to appliance version 8.8.5/agent version 5.2.5 or greater.
  2. Custom Ignored Adapters List: Add the vendor OUI or MAC address of the virtual adapter to the Custom Ignored Adapters list. This prevents the creation of new adapter records when a new MAC address for a virtual adapter is detected.
  3. Verify Agent Installation: Ensure that the agent is correctly installed on the host machine.
  4. Contact Support: If the issue persists, contact the Technical Assistance Center for further troubleshooting.
Best Regards
New Member
August 25, 2026

Same issue here - did you find a fix to this? only 1 computer is having same issue

 

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